1. Field of the Invention
The present invention relates to a method and apparatus for spatially coordinating Computer Aided Design (CAD) drawings for storage and manipulation and, more particularly, to a systematic, integrated and accurate method of spatially coordinating, storing and manipulating CAD drawings with a Master Dimensional Plan file. The method of the invention coordinates the location of plans, elevations, and sections in a single unified spatial layout referenced to a Master Dimensional Plan file (referred to herein as the “MDP” file) and uses specific “tools” to design, manipulate and present the information as two-dimensional drawings. Such tools include a method of moving between CAD drawing files using standard architectural graphic symbols as icons without using the file open dialog box, thus allowing the user to move through CAD drawing files without needing to know the underlying CAD file structure.
2. Description of the Prior Art
Computer Aided Design (CAD) drawings are vector diagrams of objects. These drawings exist in the computer program in “space” which is known in different CAD programs as “model space” for AutoCAD or “working space” for MicroStation, and the like. This application will use the term “working space” to refer to this space and will also use MicroStation terminology in describing the function and operation of the system. For purposes of this description, MicroStation SE version 5.7 with its user's guide conventions will be used. Alternative versions of MicroStation and other CAD programs, such as AutoCAD, would use the equivalent tools for implementing the method of the invention. The vector models are drawn in “full scale” in working space. When they are printed, they are reproduced in various scales for construction or design documents in order to fit on various sizes of media. These scaled reproductions are called “paper space” in AutoCAD.
A problem with existing CAD software systems, such as MicroStation and AutoCAD, is that there is no standard method for spatially locating CAD drawing files relative to each other in working space. This is particularly true of locating drawing files of the z-axis with respect to the plan files of the x-axis and y-axis. In other words, there is a need in the art for a way to consistently locate files with varying z-axis such as sections and elevations so that they have a specific spatial relationship to plan files.
Because conventional CAD drawing files are presented on the viewing screen or on printed documents in two dimensions, what is needed is a system to relate the files that are in the x-y axis with those that are in the z-axis. Although drawings may “appear” three-dimensional with systems such as renaissance perspective or axonometric drawings, drawings by their nature are two-dimensional.
Generally, drawing files can exist in the exact same x-y coordinates. Thus, for example, drawings such as a 1st floor plan and the 1st floor electrical plan can be located in the same coordinates in separate files. These same coordinates can contain innumerable drawing files that exist in the same spatial location. However, only a limited number can be viewed simultaneously in the same space on the display in an understandable fashion.
Presently, the U.S. National CAD Standards include a Uniform Drawing System from the Construction Specifications Institute (CSI), CAD Layer Guidelines from the American Institute of Architects (AIA), and Plotting Guidelines from the CAD Geographic Information Systems (GIS) Technical Center and U.S. Coast Guard However, none of these standards provides a method for locating drawing files systematically with respect to each other in working space.
While programs such as AutoCAD allow one to reference any particular point of a drawing back to a point where the X, Y and Z axes are all zero, programs such as AutoCAD do not provide a method for systematically relating all the drawing files of projects together spatially in working space.
The problem of where to locate drawing files spatially is crucial to accurately designing and manipulating the object represented in the drawing files. For example, in architectural drawings, if floor plan files are not aligned correctly with the structure files, errors or confusion may occur during construction. Further, if elevation files do not align with the plan files correctly, the openings containing windows may not be properly sized or coordinated with other systems. It is known in the CAD art that different drawing files can be located together. For example, elevation files are located on top of section files. However, this approach does not provide a systematic way to coordinate different types of drawing files such as a plan file with elevation files. A solution to this problem is needed.
The present inventor has further observed that moving between CAD files in conventional CAD systems is difficult because it requires the user to be intimately familiar with the file structure and organization. This is undesirable, particularly in the case of larger architectural projects where multiple persons access the drawings at different times. A methodology is further desired that makes moving around the architectural views of an object more intuitive. Preferably, such a method will allow for easy navigation amongst coordinated CAD views of an object.
The present invention organizes CAD drawings together into a unified system to address these and other shortcomings in the art.